I looked at that there's a lip on the bottom edge that fits there.

 

Is anybody sure about the 99's having a thicker valley cover, and which models would fit that are thinner.

 

your knock sensors have to stay there, you cant move them. plus you cant use the newer style knock sensor bc its a 2 wire setup vs the 1 wire.
also what you do mean there is a lip? can you use something to cut it down and lay the wires there? can you get us some pics of the way the intake sits on the heads and such?

 

[QUOTE=iamkeniff;4599186]your knock sensors have to stay there, you cant move them. plus you cant use the newer style knock sensor bc its a 2 wire setup vs the 1 wire.
also what you do mean there is a lip? can you use something to cut it down and lay the wires there? can you get us some pics of the way the intake sits on the heads and such?

I knew the knock sensors couldn't be moved, I can try to take some pics but I always have trouble posting them.

You can kind of see how the bottom is made in this picture. Near my toe is the bottom of the intake face that mates to the heads.

 

Technically you can relocate them to the side of the block like the LS2...just have to drill and tap. They should function just fine however you will need to lengthen the harness wires.



To the OP, what bolts are holding down your valley cover? If you are using the stock bolts, you may not be fully seating the intake which may give the impression that it is hitting the x-over tube or the K-sensor wire. You may need to purchase some flat hex cap bolts which are lower profile. Regardless, you should have room to squeeze the slim wire under the intake if you take it out of their "loom".

LS6 Valley with the low profile hex bolts:




Another way to gain a few thousanths of clearance is to ditch the thick steel and rubber valley gasket and use permatex gasket maker per instruction. Pic of the thick steel and rubber gasket:



Is there any way you can grab some pictures for the group???

 

I would really have to investigate Krambo’s suggestion of using gasket maker sealant in lieu of the factory steel embossed valley cover gasket. It’s not like it will be exposed to direct contact with oil and shouldn’t experience any issues. It very well could be all you need to make things work.

In regards to relocating the knock sensors, just as Krambo suggested, it can be done, but besides drilling and tapping to relocate them to an area similar such as a Gen IV, you would need to use the knock sensors correct for your year model (Gen III) and not sensors for a Gen IV. The harness extensions are easily available. Tuning could also be required due to changes in sensitivity from the repositioning of the sensors.

 

Krambo, I was looking at taking that thick gasket out and making my own, That would probably help also, That would definitely be cheaper than having the valley plate milled .050, I'm at work on a tug until the 28th I'll try to take a few more pics. I haven't been concentrating too much on it lately but when deer season and the holidays are over it will be my priority item. On the right side where the manifold meets the head I had to have .050 shaved from that lip on the heads.

 

is that for l92 style heads?

 

No I checked the numbers 2 times, it's for a 4.8, 5.3& 6.0 with cathedral port heads. I thought it was for the engines with the knock sensors on the side. It's just made to fit on an engine with stock heads. the designers left no room for mods, guess they thought this was the only mods we needed. HAHA what a bunch of dipsh*ts. Thanks for the info about mounting the sensors on the side. I might look into that, I have HP Tuners so I can adjust the sensitivity of the sensors. I guess this is all a part of Hot Rodding.

 

What brand TB do you have?

Thanks.